Post-Earthquake Reconnaissance: a Structural Engineer’s Perspective

Silvia Mazzoni

Submitted August 15, 2017, SCEC Contribution #7888, 2017 SCEC Annual Meeting Talk on Wed 11:00

Post-Earthquake Reconnaissance gives a first-hand opportunity to observe the effects of an earthquake on a human scale. During a reconnaissance, we gather data and knowledge, as well as an understanding and appreciation of the interdependencies between the different aspects of a society, or fields of study. Seismologists and geotechnical engineers collect field data that helps to understand the mechanisms involved in fault mechanics, wave propagation, and site amplification. As they compare different geologic regions and locations with respect to the seismogenic source, they identify source, path and local effects. Structural engineers look at the response of structures, such as buildings and bridges, and evaluate the interaction between these effects with the structures’ vulnerabilities and strengths to assess the mechanisms controlling structural response. To evaluate different building characteristics, a structural engineer looks at the response of a cluster of structures that are expected to have similar site response and determines the cause of the different structural response. During reconnaissance, we often observe adjacent buildings with very different responses, where one building may have no damage, the other may have collapsed -- the differences may be as obvious as the fact that one was strengthened while the other wasn’t. In this case, we learn the effectiveness of strengthening. In other cases, where differences in response are not as drastic, nor obvious, we look at the hidden details to learn about structural mechanics. That gained knowledge improves our building practices and policies. The one feature of an earthquake which structural engineers find only in reconnaissance and not in the laboratory or computer simulation is the human component: the story of the three little pigs isn’t about what type of building is strongest, but about the type of effort people, and society, invest into their infrastructure.

Citation
Mazzoni, S. (2017, 08). Post-Earthquake Reconnaissance: a Structural Engineer’s Perspective. Oral Presentation at 2017 SCEC Annual Meeting.


Related Projects & Working Groups
Earthquake Engineering Implementation Interface (EEII)